[PATCH v3 14/43] drm/bridge: analogix_dp: Check AUX_EN status when doing AUX transfer

Thierry Escande
2018-01-30T20:38:00Z

From: Lin Huang <hl@rock-chips.com>

We should check AUX_EN bit to confirm the AUX CH operation is completed.

Cc: Stéphane Marchesin <marcheu@chromium.org>
Signed-off-by: Lin Huang <hl@rock-chips.com>
Signed-off-by: zain wang <wzz@rock-chips.com>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
---
drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c | 25 +++++++++++++----------
1 file changed, 14 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
index 9df2f3ef000c..e78c861b9e06 100644
--- a/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
+++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
@@ -1073,9 +1073,9 @@ ssize_t analogix_dp_transfer(struct analogix_dp_device *dp,
{
u32 reg;
u8 *buffer = msg->buffer;
- int timeout_loop = 0;
unsigned int i;
int num_transferred = 0;
+ int ret;

/* Buffer size of AUX CH is 16 bytes */
if (WARN_ON(msg->size > 16))
@@ -1139,17 +1139,20 @@ ssize_t analogix_dp_transfer(struct analogix_dp_device *dp,

writel(reg, dp->reg_base + ANALOGIX_DP_AUX_CH_CTL_2);

- /* Is AUX CH command reply received? */
+ ret = readx_poll_timeout(readl, dp->reg_base + ANALOGIX_DP_AUX_CH_CTL_2,
+ reg, !(reg & AUX_EN), 25, 500 * 1000);
+ if (ret) {
+ dev_err(dp->dev, "AUX CH enable timeout!\n");
+ return -ETIMEDOUT;
+ }
+
/* TODO: Wait for an interrupt instead of looping? */
- reg = readl(dp->reg_base + ANALOGIX_DP_INT_STA);
- while (!(reg & RPLY_RECEIV)) {
- timeout_loop++;
- if (timeout_loop > DP_TIMEOUT_LOOP_COUNT) {
- dev_err(dp->dev, "AUX CH command reply failed!\n");
- return -ETIMEDOUT;
- }
- reg = readl(dp->reg_base + ANALOGIX_DP_INT_STA);
- usleep_range(10, 11);
+ /* Is AUX CH command reply received? */
+ ret = readx_poll_timeout(readl, dp->reg_base + ANALOGIX_DP_INT_STA,
+ reg, reg & RPLY_RECEIV, 10, 20 * 1000);
+ if (ret) {
+ dev_err(dp->dev, "AUX CH cmd reply timeout!\n");
+ return -ETIMEDOUT;
}

/* Clear interrupt source for AUX CH command reply */
--
2.14.1